Pyrophoric metal alloy.



UNITED STATES PATENT UFFl@E GEORG FRIEDRICH HOFMANN, OFMUNICH, GERMANY.

PYROPHORIC METAL ALLOY.

-No Drawing.

Specification of Letters Patent.

Application filed December 29, 1910. Serial No. 599,884.

Patented 0011:. 2d, Mill.

To all whom it may concern:

Be it known that I, Gnone FRIEDRIC HOFMANN, manufacturer, a subject of the King of 'Bavaria, residing at Bayerstrasse .57/59, in the city of Munlch, in the Kingdom of Bavaria, in the German Empire, have invented certain new and useful Improvements in a New Pyrophoric Metal Alloy; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Pyrophoric metal'alloys which consist of manganese and antimony are known. These metals certainly exhib1t good pyrophoric properties, but are not adapted for the ignition appliances of various kinds generally employed. The reason of this is that fine particles of these substances cannot be removed by friction to a sufficient extent with the ordinary'frictional means. Sparks can-- duoed if, in order to make these metals soft,

a suitable or softer metal, for instance lead or the like, is simply added thereto. Such additions also seriously affect the pyrophoric property of the metal, so that it is no longer adapted for igniting combustible gases. v 7

Now in accordancewith this invention the pyrophoric metallic alloy of manganese and antimony has only added to it a small quantity of metallic cerium, for instance about 5% of metallic cerium sufiices to considerably reduce the hardness of the manganeseantimony without injuring its pyrophoric property. On the contrary, very good ig- -n1ting sparks are produced by filing the metal with a file or a friction wheel of the usuaLkind. Such a pyrophoric metal alloy has the advantage that it can be used in practice. It sparks better than the simple antimony and manganese alloy. It may be more easily filed without injuring the files or filling up their teeth, and remains unaltered in the air. The particles removed by friction burn with a yellowish light and have an excellent igniting action. .The addition of metallic cerium may be made of course to'more than the percentage of 5% stated as. an example, but a considerably higher percentage is not necessary. 'It will .be' understood that the pyrophori-c property of the alloy thus formed is due largely to 'the antimony and manganese, the purpose of the cerium being to soften the alloy without altering the pyrophoric property to any appreciable extent. It will thus be seen that this alloy is different in its nature from one in which the'pyrophoric property dends u on the cerium alone as is the case in the a oy of iron and cerium which contains approximately 70% of cerium and 'ong 30% of iron.

ving now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declarethat what I claim is l. A pyrophoric 'metal alloy consisting mainly of manganese and antimony with a small addition of metallic cerium.

2. A pyrophoric metal alloy consisting of manganese, antimony, and cerium.

In testimony whereof, I have afiixed my signature, in presence of two witnesses.

GEORG FRIEDRICH HOFMANN Witnesses: I

I-IENRY'HAsPER, Womnmau HAUIT. 

